/*************************************************************************
	> File Name: 7.P1258.cpp
	> Author: hug
	> Mail: hug@haizeix.com
	> Created Time: 二  2/11 21:44:33 2025
 ************************************************************************/

#include <iostream>
using namespace std;

double s, a, b, EXP = 0.00000001;

double TA(double x) {
    return x / b + (s - x) / a;
}

double TB(double x) {
    double y = 2 * x / (a + b) * a;
    return 2 * x / (a + b) + (s - y) / b;
}

double binary_search() {
    double l = 0, r = s, mid;
    while (l + EXP < r) {
        mid = (l + r) / 2;
        if (TA(mid) > TB(mid)) l = mid;
        else r = mid;
    }
    return l;
}

int main() {
    cin >> s >> a >> b;
    double x = binary_search();
    printf("%.6lf\n", TA(x));
    return 0;
}
